feat(desktop): group slash menu commands

[RaspberryLee]

Summary

• Group slash-menu entries so built-in desktop and agent commands appear before personal skills.
• Add semantic icons for built-in commands and a dedicated skills section with a localized personal-skill badge.
• Preserve keyboard navigation and expose listbox/option semantics for assistive technology.

Feature Quality Contract

• Changed surface: desktop chat composer and desktop locale strings.
• Tests added or updated:
  • Component coverage for system-first rendering, the skills section, personal badges, and keyboard selection.
  • Utility coverage for stable system/skill grouping and ordering.
• Coverage evidence:
  • Focused changed-line coverage: 100% (145/145 executable changed lines; threshold 90%).
  • ChatInput.tsx: 118/118; composerUtils.ts: 22/22; locale additions: 5/5.
• E2E / live-model evidence:
  • Manual Windows Electron smoke: opened the composer, entered /, and verified system commands precede the personal-skills section.
  • Live model: not run (untrusted fork / no provider).
• Known risk / rollback:
  • The full local gate is not green because of failures outside this diff; details are recorded below. CI should rerun the selected deterministic gates in a clean environment.
  • Rollback is the single commit in this PR.

Verification

• bun run check:impact — passed; selected desktop, chat-contract, and coverage checks.
• cd desktop && bun run test -- --run src/components/chat/composerUtils.test.ts src/components/chat/ChatInput.test.tsx — 54 passed.
• cd desktop && bun run build — passed.
• Focused V8 coverage with the gate's changed-line algorithm — 100% (145/145).
• Same-area production changes include matching component and utility tests.
• No CLI-core, provider/runtime, persistence, coverage-policy, or quarantine-policy files are changed.

Full-gate notes

bun run verify was attempted but is not reported as passing:

• With the Node 26 Web Storage compatibility flag applied, desktop tests reached 3,288 passed, 12 failed, and 2 skipped. The remaining failures were in Windows symlink-permission tests, existing theme assertions, and a workspace timing assertion; none of their files are changed here.
• The WebSocket contract suite passed 32/32. The conversation contract suite passed 100 tests, with three fixed 5-second worktree-startup timeouts.
• The standalone coverage gate passed four suites, but its sandbox strips NODE_OPTIONS; under Node 26 this reintroduced the unavailable-localStorage failure and prevented desktop LCOV generation. The focused sandboxed coverage run above produced 100% changed-line coverage.

Risk

• This PR does not touch CLI core paths.
• Production behavior changes include matching tests.
• Coverage baselines and thresholds are unchanged.
• Quarantine policy is unchanged.
• Provider/runtime behavior is unchanged.

[github-actions]

PR quality triage

Changed areas: area:desktop

CLI core policy: No CLI-core policy block detected.

Missing-test policy: No missing-test policy block detected.

Coverage baseline policy: No coverage-baseline policy block detected.

CLI core files:

• none

Coverage policy files:

• none

Required check plan:

• See PR Quality / scope-plan; it is the single source of truth for selected jobs.

Test coverage signals:

• No obvious missing-test signal from changed paths.

Risk notes:

• No special risk notes from changed paths.

Hard merge gates come from the deterministic GitHub Actions contract lanes above.

[NanmiCoder]

Thanks